This invention relates to hinged covers and in particular relates to articulated hinged covers for copying machines used in offices and the like locations.
An office copying machine generally provides a rectangular platen framed by the chassis of the machine. Articles to be copied are placed face down on the platen in order to enable illumination of the article from the interior of the chassis for imaging purposes. A swinging cover is provided on top of the copier chassis to be swung down to a position covering the platen and to be swung up to an open position to allow articles to be placed on the platen.
In the closed position, the cover may urge an article on the platen into close contact with the platen to obtain a better copy and in the closed position the cover protects the platen which is usually made of photographic glass from scratches which would be reproduced by the copier. In the closed position the copier also protects the user from the strong illumination normally required by modern copiers.
When the cover is in the open position, articles may be removed from and placed on the platen.
Copying of articles thicker than a few sheets of paper such as books, magazines, etc., poses problems in the design and construction of copier covers. A cover which is hinged with only one pivot along an edge thereof cannot be moved to lie flat against the platen, the thickness of the articles preventing such disposition. In this case, the free end of the cover usually is left spaced from the platen with the cover forming an angle with the platen, the angle being determined by the thickness of the article being copied.
U.S. Pat. Nos. 4,157,222 and 3,630,620 disclose covers for copier platens which are essentially plates hinged at their rear margin to accommodate articles of varying thickness. U.S. Pat. No. 4,157,222 includes an attaching portion 14 secured to the copier top adjacent a rear edge of the platen, a narrow portion 20 being hinged to the attaching portion 14 and a hold-down portion 16 being hinged to the narrow portion 20. Hold-down portion 16 extends over and covers the platen. The two joints connecting the narrow portion 20 with the attaching portion 14 and the hold-down portion 16 permit the hold-down portion 16 to be disposed above the platen over articles of varying thickness in substantially parallel relationship to the platen. U.S. Pat. No. 3,630,620 provides a cover 12 having two like rectangular plate-like members 31 and 32 hinged along a common joint 34 and covering a copier platen. The rearmost edge of plate 31 is connected to a support bracket 41 by a hinge 44 with bracket 41 being connected to a joint 42 spaced above the plane of the platen at the rear of the platen.
In both of these patents, opening the cover and closing it on articles of varying thickness is awkward because of the two freely swinging joints.
U.S. Pat. No. 3,997,265 discloses a cover 10 formed of a box-like housing 22 having an open ended chamber 34 facing downward on a platen 12. Housing 22 has a substantial height to accommodate an inner member 26 disposed within the chamber 34 in parallel relationship to the platen 12, member 26 being slidably connected in the interior of the cover 10 to accommodate articles of varying thickness while the lower peripheral edges of the cover remain in contact with the copier top. The cover 10 is hinged at its rear lower edge to the copier top which enables the cover to be opened and closed around that one hinge, but the cover has a substantial height above the copier top to accommodate articles of varying thickness in addition to the inner member 26 and its associated mounting hardware.
The invention herein provides a cover which is easily opened around a single pivot at the rear of the cover and which is closed over articles of varying thickness while maintaining a low profile on a copier top.